01/13/2014 (10:00PM – 11:00PM) (Monday) : WHO IS THE MOLE? – FRANK WHALEY GUEST STARS – The entire FBI team is under investigation as internal affairs tries to find the mole. Elsewhere, Red (James Spader) is missing and conducts his own investigation into who betrayed him. Meanwhile, a serial killer from Liz’s (Megan Boone) past, “The Good Samaritan” (guest star Frank Whaley) strikes again. Liz is allowed to join the hunt for the killer as Cooper (Harry Lennix) knows Red will likely reach out to help knowing how much this unsolved case means to Liz. Diego Klattenhoff and Ryan Eggold also star.